1. J#

2. J/Direct (Java/Direct)

3. J2EE (Java 2 Platform, Enterprise Edition)

4. J2ME (Java 2 Platform, Micro Edition)

5. J2SE (Java 2 Standard Edition)

6. Jabber

7. jack plug

8. Jaguar

9. JAR file (Java ARchive file)

10. Java

11. Java 2

12. Java servlet

13. JavaBeans

14. JavaOS

15. JavaScript

16. Jaz drive

17. JCL (Job Control Language)

18. JDBC (Java Database Connectivity)

19. JDC (Japanese Digital Cellular)

20. JDK (Java Development Kit)

21. JEP (Joint Electronic Payment Initiative)

22. JET (Joint Engine Technology)

23. jet printer

24. JFC (Java Foundation Classes)

25. JIC (Just in case)

26. Jigsaw

27. Jini

28. JIT (Just-In-Time compiler)

29. jitter (1)

30. jitter (2)

31. JK (Just kidding)

32. JMAPI (Java Management API)

33. JMS (Java Message Service)

34. job

35. job ticket

36. jog wheel

37. join

38. Joomla!

39. journal

40. journaling

41. journaling file system

42. journaling file system

43. Jove

44. joypad

45. joystick

46. JPEG (Joint Photographic Experts Group)

47. JPG

48. JRE (Java Runtime Environment)

49. JScript

50. JSP (1) (JavaServer Pages)

51. JSP (2) (Jackson Structured Programming)

52. JTAC (Japanese Total Access Communication)

53. JTAG (Joint Test Action Group)

54. JTAPI (Java Telephony API)

55. Jughead

56. jukebox

57. jump

58. jump instruction

59. junk e-mail, junk mail

60. justification

61. justify

62. JVM (Java Virtual Machine)

63. JXTA (Juxtapose)